Electric-lamp fixture.



A. C. McWiLLlAMS.

ELCTRIC LAMP FIXTURE.

APPLICATION FILED APR.2o, I9I2.

` Patented July 6, 15H5.

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ELECTRIC-LAMP FEXTU'RE.

ifpecication of Letters Eatent.

Patented July 6 1i9l5.

Application filed April 20, 19'12. Serial No. 692,076.

To all '1.0710713'. it 'may concern.'

Be .it known that l. ARTHUR C. Mcliln'.- mans, a citizen ot'- the United States., residing at Chicago, in the county of @ook and State of: Illinois. have invented a certain new and useful lmprovunent in Electric- Lamp Fixtures', of which theefollowing is a specification- My invention relates to electric lainp lire' tures and the ologect of the invention is to provide a simply constructed fixture capable of being adjusted in various ways to suit conditions of use.

Among other adjustments may be noted the'vertical adjus ment of the lamp socket with reference to the shade holder and shade to accommodate lamps of various sizes, and shades of various forms and for various situations; also the adjustment of the shade holder with referenceto the stem of the ixture and also the'adjustment of the canopy with reference to the ceiling or wall upon which the fixture is to be attached. 1

Another object of the invention is to provide a fixture so constructed that it may be readily taken 'down for refinishing, inspection or repair and be readily replaced with a minimum of time and trouble.

Contributing to these general objectsit is my purpose to provide certain advantageous 'details ot construction which will be hereinafter more particularly described and claimed.

l accomplish my objects by the mechanism illustrated in the accompanying drawings in whichv Figure l is an axial section. Fig. 2 is an elevation of some of the internal parts of the mechanism. Fig. 3 is a transverse section taken on line 2%#8 Fig. l. Fig. 4 is an axial. section showing one of the connector bars and associated parts inclosed Iin the stein. Fig. 5 is a transverse section taken on the line 5-5 Fig. 1. Figs. 6 and 7 are perspec-l tive views of the connector bars. S is a perspective view of the clip employed on the connector bars, and/Fig. 9 is a perspecceiling the parts will be described as if thev fixture were in this position-and the chief component parts arranged in vertlcal posi,

tion. lit will be understood, however, that the fixture is equally operative when attached to a. wall.

ln the present form, selected to illustrate the invention, the stem is formed in two parts, the terminal l, formed of metal and internally threaded to screw upon. the -stationary fixture stub 2, and the stem-proper ,3, consisting` of any suitable insulating material which is preferably dove-tail molded to the terminal The' lower portion of stern is cylindrically chambered, axially, and thus makes a sliding fit with the lamp socket 4. In the preferred construction, said socket is provided 'with an internal rnetallic bushing' 5, which is threaded to receive the stern of the .lamp G. A. terminal piece 10 is mounted in. socket 4 in position to contact the central terminal of the lamp, said terminal piece being connected by a` screw l1 or otherwise to the lower connector bar.

1:2. 'The metallic bushing is electrically connected by the screw l5 or otherwise to the lower connector bar 16 of opposite polarity to bar l2. Said connector bars make sliding connection with the upper connector barsand are provided with conductive terminalsl 19 whereby they may he electrically connected to the supply conductors 20. l

Means are provided for regulating the pressure between the contacting surfaces of theA connector bars above mentioned7 for regulatingI the friction between them. The means for thus regulating' the friction are shown in Figs. l. 8 and elsewhere,A and include a clip 25 which vis Ushaped and pro` vided with a slot 26 at the bend in the bottom 'for receiving a. pair of the connector bars. lt the upper end, the lower connector bars have a` springr bend 27, having' an aper- 1 ture QS adapted to receive tension screws 29, the latter being' shown especially ifi-Figs l, 3, 4c and 5. These screws pass through apertures and 3l in the clip, the aperture 30 being loose enough to loosely receire the screw while the aperture 3l is threaded to coact with the screw. -'l`he upper hars 18 have a longitudinal slot 33 through which the tension screws pass. The result is two fold, iirst the amount of 'friction between the sliding connector bars may he regulated, second the clip, as it supports the two ends of the tension screw always holds it horizontal, thereby causingl it to travel Yfreely in slot 33.

llrom the oregoing it will be seen that the lamp socket and lamp are' ve tically adjust able in the stern and that the lamp will be provided with current w en the parts are at any elevation within the range of adjustment.

l will now descrihe.the manner of supporting1 the canopy and shade holder and adjusting them to the positions required.

A clamping collar 37 shown in perspective in Fig. 9 encircles the stem 3 and has a. slot 3S in its side for rendering; the upper edge oi the collar contractile. At the upper edge said collar is provided with two ears 39 one ot which is screw threaded to take a. clamping screw 4l() best shown in Fig. 3. The other ear is apertured to loosely receive the screw; consequently the collar may be clamped at any desired elevation upon stem 3 below the feed wires Q0 and above the annular shoulder 43 'formed in the stem as best shown in Fig. l. This shoulder' is not an essential feature of the construction but is desirable as it forms a` stop for limiting the downward movement oli the collar 37. Said collar has a vertical slot for receiving the .latch 46 shown in detail in Figs. 2 and. Latch 46, when in acting position, has its major portion vlyingr Within I a chamber' 47 formed within' stem 3 but projectsthrough slot above mentioned and through a corresponding slot 48 formed near the upper end of the cylindrical portion of the shade holder 50. Slot 4S is curved as best shown in Fig. 2 and receives a pin 5l Vsecured to and projecting from the side of ring' 37. The result is that the ring-and shade holder are connected by what is termed a bayonetljointl When the latch is drawn down far enough to lie within bot-h of the slots 45 and i8 in the collar and shade holder respectively, relative rotation of the collar and shade holder will be prevented and, on account of thepresence of the hayonet joint will prevent the collar and shade holder from beingdisconnected. lWhen however, the latch is raised by` screw high enough to leave slot 48, said collar ahd shade holder may he disconnected. Thisl interrelati'on Will be ob f'ious upon reference to 2. Screw by which the Vertical posi-A tion. of latch 46 is controlled is preferably housed Within stem 3 and l`projects down to trician'.

tresses the hottom of the latter where the screw head 56 is accessible 'from the lower end of the fixture when the shade 5S is not present. its the open end of slot t8 is at the top, gravity tends to cause the latch to enter and remain in it. 1nd hence the latch may safely be operated by merely pushingthe screw up or down to :ause the latch to enter or leave said slot.

rlhe latch and associated parts are norm mally inclosed by the canopy G0. rThe shade holder may assume any suitable form at the lower end adcc'uate for sumortine" the i e I shade. An annular head 62 is former. at a convenient vpoint near the upper end of the shade holder, and upon this bead rests the lower extremity ot the canopy. The elevation of the canopy therefore depends upon the elevation of the shade holder, and the elevation oit the shade holder depends upon the vertically adjustable collar 37. lt will be understood by those who have had'practical experience that theexposed surface of the ceiling will. vary with respect to the elevation ot' the lfixture stub Q; hut as the canonv and shade-holder are 'vertically adjustable hy reason ot the vertical adiustahility ot the clamping; collar B7. a considerable range of variation in the ceiling.,r is easily compensated for.

ln operation when it is desired to disasscmble the parts all that is necessary is to lift the latch HS out ot slot 48, whereupon by slightly rotating the shade holder, the latter may be disconnected from collar 37 and the shade. shade holder -and canopy may he simultaneously lowered, and removed. Thewiring connections are then fully exposed and by disconucctinpr the cnil of the `feed wires from the terminals 19, the entire remaining portion ot the fixture may he removed by merely unscrewingr the terminal l from the stub 2. The extreme ease with which the shade holder and canopy may he lowered or replaced is ot great practical advanta'ge, yfor it is frequently desiru able to inspect the wire connections for various reasons. Furthermore, fixtures are apt to tarnish and require replating'or refinishing and with the ordinary .fixtures this is not possible without requiring considerable labor and trouble on the part of an elec- `With my construction' also, it is possible, by carrying in stock a few patterns of shade holders and a few patterns of cano- 'pies to produce a .great variety of combi nations of the two, thus with little expense avoiding; the monotonypf identical fixtures throughout the building. y

As the parts l and" 2 virtually constitute a single piece, it will' be seen that the bull; of the fixture is compri-sed ot but three main parts in addition to the lamp socket, to Wit': the canopy, shade holder and stem.

ln adjusting the lamp socket vertically to 'roo the elevation required. On account of the formation of the connector' bars, the socket and lamp will securely maintain any elevation to which they are brought. If the buildings in which the fixtures are mounted' are subject to great vibrations as in a factory, the friction between the connectors may bev increased to any desired extent by adjusting the tension screws Conversely for ordinary office buil-dings, this friction maywith safety be reduced to a minimum thus rendering the lamp vertically adjustable with the expenditure of little energy on the part of the user.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is: A

l. In a lamp fixture, the combination of a stem, a lamp socket slidable therein, a pair of connector bars connected to the terminals of the socket, asecond pair of connector bars secured to the stem and adapted to make sliding Contact with the first menw tioned pair, and means for controllably varying the amount of friction between said connector bars,

2. In a lamp fixture, the combination of a stem, a lamp socket slidable therein, a pair of connector bars connected to the terminal of the socket, a second pair of connector S5 bars secured to the stem and adapted to make sliding contact with the first men tioned pair, and a clip apertured for the reception of two cooperating connector bars, said clip being adapted to regulate the friction between the connector bars'.

In a lamp fixture, the combination of a stem, lamp socket slidable therein, a pair of connector bars connected to vthe terminal of the socket, a second pair of connector bars isecurcd to the stem and adapted to make slidingcontact with the first mentioned pair, one pair of said bars being longitudinally slotted, a clip on each two coperating bars apertured for the reception thereof and a tension screw mounted in said clips yand passing through the slots aforesaid and also passing through apertures'in the connector bars which coperate with the ones which` are slotted.

4. In a lamp fixture, the combination of a stationary stem, having a longitudinal center bore for a considerable portion of its length, a lamp socket' slidable in said center bore, a pair of connector bars connected to 80 the terminal of the socket, a second pair of connector bars fastened to the stationary stem and adapted to make sliding contact with the first mentioned pair, said connector bars being located chiefly within the bore of the stem and the stationary bars having 5. In a lamp fixture, the combination of a stationary stem, a .collar mounted thereon,

a shade holder encircling said collar .and connected thereto by, a lbayonet joint` :saidcollar and shade holder'having slots adapted toregister with each other, and a latchadapted to penetrate said slots to prevent relative rotation of the collar and shade holder to therebyprevent the disconnecting of the bayonet joint.

G. In a lamp fixture, the combination of a stationary stem, a collar mounted thereon, a shade holder encircling said collar and connected thereto by a bayonet joint and a latch slidingly engaging said. collar, said latch being vertically movable and laterally nonmovable there being an open ended slot in said. shade holder adapted to receive said latch to prevent the shade holder from rotating and being thereby disconnected from the Collar.

7. In a lamp iixture, the combination of a stationary stem, a shade holder encircling the same, and means for attaching and detaching said shade holder from said stem,

said attaching and detaching means comprising a latch housed. for the most part in said stem and vertically movable therein,

and means for vertically moving said latch,

independently of the shade having a center bore extending the major portion of its length, commencing at the bottom, alamp socket within the center bore of the-stem and vertically adjustable with reference thereto, terminals secured to said stem for connection to electric feed wires, adjustable connectors for maintaining electrical connection between the lamp socket .and the terminals on the stem and a shade holder and a canopy both encircling said stem and forming a housing for the above mentioned parts.

10. In a lamp fixture, the combination of a stationary stem of insulating material sub- Vstantially cylindrical on the outside and having a center bore extending the major- Agol-tion of its length, commencing at the ottom, .a vertically adjustable lamp socket lO ently of the lmnp socket, and a canopy enmme@ circling said stern and resting lightly upon the same to be supported theieojy".

@ln Witness whereof, l have hereunto subscribeamy name in the presence of two Wit messes.

ARTHUR C. llyIo/YLLIAMS lllitnesses:

Hou/'ARD M. @0X5 Ermua L. WHITE. 

